The correlation analysis of RCPs impeller geometrical parameters and optimization in coast-down process

Correlation analysis and partial correlation analysis are conducted for RCPs impeller geometric parameters and hydraulic performance in this study by orthogonal test, the goal of which is to reduce energy loss as well to prolong the coast-down time of the reactor coolant pump during the coast-down process. The correlation and partial correlation analyses combined reveal that impeller geometrical parameters are not independent of each other but rather mutually reinforcing or weakening in terms of certain performance indicators. Such analyses do not reflect the coupling relationship and effect size between different geometric parameters. The impeller design is optimized by selecting the optimal parameter combination as-defined by correlation analyses, then validated by an experiment. The optimized impeller is shown to lengthen the coast-down time of the pump rotor by 10%, and to significantly enhance coast-down process performance. (C) 2020 Elsevier Ltd. All rights reserved.